Parking on the Edge of Tomorrow: How to Design Parking for an Unknown Future

Trends & Innovation

The advent of driverless cars has led many to predict a dramatic change in parking demand as well as the way we store vehicles in the future. However, as with any major shift in urban infrastructure, the crystal ball is still shrouded in mist. Will we ultimately live in a world where autonomous vehicles are owned by transportation network companies (TNCs), or will we cling to our car ownership even if we relinquish the steering wheel?

Whatever direction we ultimately adopt will have a profound effect on urban infrastructure and parking in particular. But a future shift of parking demand does not change the fact that right now demand is still high and well-integrated parking is crucial to a project’s success. Given the longevity of a new structure and the significant impact parking has on land use and project costs, owners naturally want to ensure that their investment is as viable years down the road as it is today, which raises a challenging question: how do we design parking for a future that isn’t yet clear?

The good news is there are steps we can take today that will help us prepare for that unknown tomorrow. However parking ultimately evolves, one thing we can be certain of is that it will densify. When you take humans out of the driving and parking equation, much of the parking infrastructure we design for humans will be eliminated, requiring less space to park the same number of cars. Therefore, if we look at key concepts with an eye towards density and efficiency, we put parking in a better position to adapt to whatever the future holds.

Think Outside the Box

Cities are already trending towards greater density when it comes to parking, and many are discovering the value of sharing parking within a community instead of viewing parking demand only as it applies to individual parcels. Parking has long been governed by traditional ratios that establish how much parking should be provided for a given use on a given site. But when we consider parking in context with the surrounding community, we can often find more efficient ways to meet demand while avoiding overbuilding.

Take for instance a mixed use development that provides office space, retail and entertainment. These uses often have peak demands that neatly offset each other, with office workers needing parking during the day and entertainment seekers looking for a space in the evenings and on weekends. Were these developments to be evaluated individually, parking supply would need to be much higher than it is when they densify by sharing the same parking inventory. If access is available to alternative forms of transportation, like mass transit or TNCs, parking demand can be adjusted even further.

This kind of thinking was applied to the Runway at Playa Vista mixed use development in Los Angeles. The final programming chosen for the project was strongly influenced by what uses could most effectively share parking, an approach that ultimately saved the developer significant cost. An office development in San Jose, California was able to cut traditional parking ratios in half after carefully evaluating projected demand and working closely with the city. Not only did this drastically reduce the parking footprint and costs, but the developer was also able to work out an arrangement that would benefit the city by providing public parking on evenings and weekends to neighboring entertainment venues.

When we densify our approach to parking by looking at it more holistically, we can develop more efficient spaces that work for us now, and require less intervention as we shift into an unknown future.

Mechanical and automated solutions take advantage of volume in a space by “stacking” vehicles on top of one another. This approach makes it possible to store more cars in a smaller volume of space.

Take Advantage of Volume

While we may not know for certain when or how drastically driverless cars will impact parking demand, we do know that less space will be needed to store them for the simple reason that humans will no longer be behind the wheel. However, as urban developments densify, costs rise, and other building constraints make supplying traditional parking more challenging, we’re already forced to find innovative ways to do more with less. This is leading to increasing proliferation of mechanical, automated and full-valet parking solutions that utilize volume rather than traditional parking stalls to meet demand.

This approach is becoming more and more prominent in dense, urban areas that face costly subterranean excavations and other building constraints that make a traditional parking solution cost prohibitive or even impossible. When viewed as a permanent solution, mechanical, automated and full-valet operations can store more cars in a smaller volume than traditional parking. In addition, this method can also provide an interim solution to meet current parking demand while providing a path for adapting the space to an alternative use whenever parking demand ultimately decreases.

Mechanical and automated solutions take advantage of volume in a space by “stacking” vehicles on top of one another, which requires floor-to-floor heights that are more compatible with human use than a traditional parking structure. Therefore, while parking demand is high, a mechanical or automated system makes it possible to store more cars in a smaller volume of space. As parking demand decreases, the equipment can be removed and the space repurposed to other uses. Because some of the design provisions necessary for this conversion are already incorporated into the initial parking design, the extra costs associated with designing for adaptive reuse are already reduced.

For an apartment complex in Wichita, Kansas called The Douglas, a mechanical parking solution was the only option to provide parking on a site with existing historic buildings with site constraints and height restrictions. Because the floor-to-floor clearances and level floor plates required to support the mechanical system are compatible with adaptive reuse, the three levels of mechanical parking in the facility could potentially be repurposed if there is a decrease in demand.

Adapt For Future Reuse

In addition to densifying parking, another way to prepare for the future is to design parking for greater flexibility. If parking demand decreases, some existing parking facilities may no longer be needed. Therefore, owners who need to build structured parking to address today’s parking needs want to be sure they are getting the most out of their investment. One method being explored is designing parking that can be adapted to other uses.

Before: The ground level of this parking structure is designed to be adapted to an alternative use.

This is an exciting concept, but it is also a costly one. Without knowing what the future really holds, finding an approach with the most potential to provide long term returns is not a simple prospect. Facilities designed for vehicles are fundamentally different than those designed for humans, which means designing a parking structure to shift from one to the other requires significant design considerations that can rapidly inflate the initial cost.

For instance, though it sounds counterintuitive, structural and occupancy loads needed to support human use are nearly twice what is required to house cars. Garages typically have lower floor-to-floor heights than what is needed for people, and park-on-ramps combined with a typical 5-6% slope in typical garages are not conducive to other uses. To modify these design standards and make them more compatible with human use requires significant upfront costs, which owners may find daunting without a guaranteed return on investment.

After: The same parking structure with the ground floor converted to retail space, retaining parking above.

Other design considerations that must be factored into the transition include the size of the building footprint. Residential use, for example, would not be very compatible with a large floor plate as it would not provide enough natural light. The location of pedestrian cores can provide another challenge. Parking structures traditionally provide this infrastructure at the corners of the building while an office layout might place it in the middle. Therefore, when designing parking with a mind towards an alternative future use, understanding what that future use will be and how people will use it is vital to the initial design.

While there are ways to overcome each of these challenges, they all have the potential to significantly add to the initial cost, even to the point of making it more financially viable to build the structure traditionally and demolish it later should demand shift. However, the impact of structural, occupancy and drainage considerations is far less on ground levels verses upper levels, meaning designing an on grade level for adaptive reuse while retaining parking above is a far more cost effective solution.

While the advent of driverless cars will certainly change the parking landscape, it won’t eliminate parking all together. Even without a clear picture of the future, we can find ways to ease our transition into the unknown by changing the way we think about parking. By looking at the challenges we face today and the innovations we’re using to navigate them, we can position today’s projects for what is to come, whatever that may be.

About the Author

Jess McInerney, SE has been creating parking solutions for over 20 years. He is a licensed engineer in 5 states. Jess is responsible for the design of over 125 parking projects and leads parking structure design for the firm. An active member in the Urban Land Institute, Jess has both written and spoken on the future of parking, the cost of designing for adaptive reuse, mixed-use parking, below grade parking and the integration of Photovoltaics into parking structures.